Periodic Reporting for period 4 - R-WAKE (Wake Vortex simulation and analysis to enhance en-route separation management in Europe)
Reporting period: 2017-10-01 to 2018-03-31
The dangers of Wake Vortex encounters in en-route flight have been traditionally considered negligible since the probability of a WV encounter has been low up to now, whereas the severity of a possible encounter has been often found not worrying. Nevertheless, several factors that may cause the increase of both the probability of encounter and the severity are changing in the context of the new Air Traffic Management proposed by SESAR.
In this background problem, the application-oriented research project R-WAKE, “WAKE VORTEX SIMULATION AND ANALYSIS TO ENHANCE EN-ROUTE SEPARATION MANAGEMENT IN EUROPE” addresses the SESAR 2020 Exploratory Research work-programme topic ER-07-2015 - Separation management and separation standards, within the area of advanced air traffic services, with the overall objective of investigating the hazard of wake vortex encounter (WVE) in the en-route airspace, and the subsequent identification and assessment of potential enhancements to the current separation schemes, aiming to enable operational improvements steps in traffic and trajectory management, in current and future ATM scenarios, with expected benefits in the performance areas of safety, airspace capacity, and flight efficiency of the European ATM system.
More specifically, the project has focused on the ATM problem that the current separation minima standard applied in en-route operation is 5NM in horizontal and 1000 feet in vertical for all aircraft types and conditions, and this is considered over-conservative for some aircraft categories, while not enough in other cases (e.g. wake encounters have been reported up to 25NM behind big generating aircrafts), hence an opportunity to enhance the en-route separation schemas is envisioned upon the assumption that air traffic controllers can consider specific operational conditions (e.g. the involved aircraft types) to derive more specific traffic separation instructions. This focus was formulated as the research question: 'What wake separation minima reductions can be applied in specific and clearly defined operational conditions to increase airspace capacity while keeping or enhancing the current safety levels and taking into account the risk of en-route WVE hazards?'
To address the research, the project overall approach is model-based simulation. A main project goal has been the development of an ad-hoc simulation system, referred as the R-WAKE System, acting as research enabler and concept validation means. Its development has been based on baseline models and tools available in the consortium partner´s background, which have been further developed and integrated into a common framework of research methodology and software tools. The achieved simulation system includes tools for weather simulation based on real historic data, traffic and trajectories scenarios generation, wake vortex generation, a wake encounters interaction assessment model that delivers high fidelity upset calculation and severity assessment, and a safety and robustness analysis method including risk models. The overall approach then follows with the due simulation and analysis of study scenarios, and the generation of the WVE hazard characterization simulation databases, usable as evidence body to identify and support new separation enhancement proposals, referred as R-WAKE Concept.
In this background problem, the application-oriented research project R-WAKE, “WAKE VORTEX SIMULATION AND ANALYSIS TO ENHANCE EN-ROUTE SEPARATION MANAGEMENT IN EUROPE” addresses the SESAR 2020 Exploratory Research work-programme topic ER-07-2015 - Separation management and separation standards, within the area of advanced air traffic services, with the overall objective of investigating the hazard of wake vortex encounter (WVE) in the en-route airspace, and the subsequent identification and assessment of potential enhancements to the current separation schemes, aiming to enable operational improvements steps in traffic and trajectory management, in current and future ATM scenarios, with expected benefits in the performance areas of safety, airspace capacity, and flight efficiency of the European ATM system.
More specifically, the project has focused on the ATM problem that the current separation minima standard applied in en-route operation is 5NM in horizontal and 1000 feet in vertical for all aircraft types and conditions, and this is considered over-conservative for some aircraft categories, while not enough in other cases (e.g. wake encounters have been reported up to 25NM behind big generating aircrafts), hence an opportunity to enhance the en-route separation schemas is envisioned upon the assumption that air traffic controllers can consider specific operational conditions (e.g. the involved aircraft types) to derive more specific traffic separation instructions. This focus was formulated as the research question: 'What wake separation minima reductions can be applied in specific and clearly defined operational conditions to increase airspace capacity while keeping or enhancing the current safety levels and taking into account the risk of en-route WVE hazards?'
To address the research, the project overall approach is model-based simulation. A main project goal has been the development of an ad-hoc simulation system, referred as the R-WAKE System, acting as research enabler and concept validation means. Its development has been based on baseline models and tools available in the consortium partner´s background, which have been further developed and integrated into a common framework of research methodology and software tools. The achieved simulation system includes tools for weather simulation based on real historic data, traffic and trajectories scenarios generation, wake vortex generation, a wake encounters interaction assessment model that delivers high fidelity upset calculation and severity assessment, and a safety and robustness analysis method including risk models. The overall approach then follows with the due simulation and analysis of study scenarios, and the generation of the WVE hazard characterization simulation databases, usable as evidence body to identify and support new separation enhancement proposals, referred as R-WAKE Concept.
During the first project period, as part of WP2 Concept Definition tasks, the project objectives and scope were elaborated in detail, addressing the research scope in terms of study scenarios, together with the specification and design of the research methodology and required simulation system models and tools.
A main outcome of this definition phase was the structuration of the research in two incremental steps, namely micro and macro level study, as way to tackle the complexity of the investigation. They are:
- Step-1, performing micro-level study, that is, the study the upsets in a variety of vortex types, aircraft types, and encountering conditions in the upper flight level, and development and assessment of an absolute severity baseline, with qualitative assessment from pilots and controllers experts, and
- Step-2, performing a macro-level study, that is, the study of the hazard risk in ATM systemic terms (ECAC-wide), that is, the frequency encounter occurrence per severity level (having the severity baseline resulted from step 1), and the mitigation effect (protection level) of the separation standards under evaluation, for both, the current schemes (i.e. unit safety case), and then the new R-wake concept separation schemes (i.e. project safety case).
The simulation system was architected correspondingly in two variants of the system:
- The micro-simulation system, consisted essentially in a Wake Interaction Assessment Model (WIAM), based on high fidelity modeling of the aircraft wings, in order to compute flight dynamics effects (upsets) of the vortex encounter.
- The macro-simulation system consisted in the full set of tools integrated under a cloud-based workflow manager to perform systemic ATM scenarios for the full European area (ECAC) (this was the initial system conception).
The closure meeting concluded the project has fully achieved to deliver its five targeted tangible expected outcomes.
That is:
1) An ATM traffic simulator that includes high-fidelity wake vortex encounter (WVE) dynamic risk models, referred as the R-WAKE system, tailored to support the project research approach, understood as a framework to assess the safety and robustness level of new separation schemes.
2) A WVE hazard severity baseline, defined as a matrix of upset parameters thresholds per severity class, developed and assessed with contributions of experienced pilots and air traffic controllers.
3) A public database of simulation results, which constitutes an evidence body to support new separation scheme proposals, containing the upset and severity class computed for a large number of encounter scenarios, involving different aircraft types, geometries, separations, and weather conditions.
4) The R-WAKE-1 concept proposal, which consists of six new separation schemes referred as en-Route Minisum Wake Separation, RMWS, designed to increase safety against WVE hazards and also airspace capacity, looking at the minimum wake separation in the three dimensions: lateral, vertical, longitudinal, and also in combined lateral-vertical, and wind-dependent dynamic separations.
5) And a feasibility and impact assessment of the concept, concluding that there is enough justification for proposing R-WAKE-1 as a new SESAR Solution in the ATM Master Plan pipeline, as a first step in a roadmap of identified incremental evolutions towards a long term R-WAKE concept.
R-WAKE-1 concept: “Optimised En-Route separation minima resulting from static Distance-Based Geometry-Based Category-Wise assessment of WVE hazards”.
A main outcome of this definition phase was the structuration of the research in two incremental steps, namely micro and macro level study, as way to tackle the complexity of the investigation. They are:
- Step-1, performing micro-level study, that is, the study the upsets in a variety of vortex types, aircraft types, and encountering conditions in the upper flight level, and development and assessment of an absolute severity baseline, with qualitative assessment from pilots and controllers experts, and
- Step-2, performing a macro-level study, that is, the study of the hazard risk in ATM systemic terms (ECAC-wide), that is, the frequency encounter occurrence per severity level (having the severity baseline resulted from step 1), and the mitigation effect (protection level) of the separation standards under evaluation, for both, the current schemes (i.e. unit safety case), and then the new R-wake concept separation schemes (i.e. project safety case).
The simulation system was architected correspondingly in two variants of the system:
- The micro-simulation system, consisted essentially in a Wake Interaction Assessment Model (WIAM), based on high fidelity modeling of the aircraft wings, in order to compute flight dynamics effects (upsets) of the vortex encounter.
- The macro-simulation system consisted in the full set of tools integrated under a cloud-based workflow manager to perform systemic ATM scenarios for the full European area (ECAC) (this was the initial system conception).
The closure meeting concluded the project has fully achieved to deliver its five targeted tangible expected outcomes.
That is:
1) An ATM traffic simulator that includes high-fidelity wake vortex encounter (WVE) dynamic risk models, referred as the R-WAKE system, tailored to support the project research approach, understood as a framework to assess the safety and robustness level of new separation schemes.
2) A WVE hazard severity baseline, defined as a matrix of upset parameters thresholds per severity class, developed and assessed with contributions of experienced pilots and air traffic controllers.
3) A public database of simulation results, which constitutes an evidence body to support new separation scheme proposals, containing the upset and severity class computed for a large number of encounter scenarios, involving different aircraft types, geometries, separations, and weather conditions.
4) The R-WAKE-1 concept proposal, which consists of six new separation schemes referred as en-Route Minisum Wake Separation, RMWS, designed to increase safety against WVE hazards and also airspace capacity, looking at the minimum wake separation in the three dimensions: lateral, vertical, longitudinal, and also in combined lateral-vertical, and wind-dependent dynamic separations.
5) And a feasibility and impact assessment of the concept, concluding that there is enough justification for proposing R-WAKE-1 as a new SESAR Solution in the ATM Master Plan pipeline, as a first step in a roadmap of identified incremental evolutions towards a long term R-WAKE concept.
R-WAKE-1 concept: “Optimised En-Route separation minima resulting from static Distance-Based Geometry-Based Category-Wise assessment of WVE hazards”.